Due to high thermal and mechanical performance, coupled with relatively low density, numerous components could benefit from the use of Ceramic Matrix Composites (CMCs) in place of metals or intermetallics. During the manufacturing processes of CMC, the fibers need to be coated in order to survive the processes as well as for mechanical properties in service. Currently, two of the primary cost-effective methods of processing ceramic matrix composite (CMC) components are chemical vapor infiltration (CVI) and polymer infiltration and pyrolysis (PIP). Another process is glass transfer molding, which is faster than CVI and PIP, but is also much more expensive and resource intensive. Each of these processes uses a filament handling device using various forms of tension control on fiber movement during processing.
In the fiber coating process, fibers are typically unwound from a spindle to begin processing. During the unwind process, tension of the filaments is carefully controlled, since too much tension could destroy the filaments while not enough tension can allow the tow to jump off rollers and mis-track. In a fiber coating process, tension can also affect filament spacing which, in turn, can affect coating thickness uniformity and mechanical properties. In a conventional filament handling apparatus, the fiber bundles often break in midstream at any place along the fiber path length and breakage often occurs due to a failure in a process of unwinding the fiber bundles from fiber bundle feeding packages. The breakage of the fiber bundle typically occurs when friction exceeds the fiber strength or one or more of a plurality of single fibers of the fiber bundle is snarled or tangled at the time of unwinding process.
Thus, a need exists for an automated device that is constantly correcting, adjusting and maintaining the unwinding process of the tow during fiber processing.